Because programs preventing prenatal HIV transmission are reaching a greater number of pregnant women worldwide and are successfully reducing vertical transmission, an ever increasing majority of children born to HIV-positive mothers are uninfected. In addition, new medical innovations and increasing availability of antiretroviral therapy (ART) have improved the health and longevity of HIV-positive parents, which means they are more likely to raise their children for many years after the initial diagnosis. For parents living with HIV (PLH), disclosing their HIV infection to their seronegative children (parental HIV disclosure) becomes an increasingly important issue in terms of well-being of parents, children and families. The global literature in parental HIV disclosure suggests that developmentally appropriate, well-planned disclosure can greatly benefit the well-being of PLH, their children and families. However, for multiple reasons including fear of stigma and the psychological burden such knowledge might place on their children, PLH often struggle about whether, when, what, and how to talk to their children about their HIV infection. Many of them do not disclose their HIV infection to children primarily because they lack the confidence and behavioral skills to appropriately and effectively accomplish this task. To date, the issues surrounding parental HIV disclosure have been understudied, particularly in low- and middle-income countries (LMICs) including China where the HIV epidemic has been steadily expanding. In this application, we propose to adapt relevant components from two evidence-based programs developed in the US to produce a theory-driven developmentally appropriate parental HIV disclosure intervention in Guangxi, China, where we have built a strong research infrastructure and community collaboration through NIH-funded research since 2004. The proposed project consists of three main operational phases. Phase I includes formative research to examine current practices, barriers and facilitators, cultural influences, and effects of disclosure on PLH and their children. The data to be collected in this phase will complement the data we have collected and will inform the adaption of intervention content and delivery modality. Phase II includes the development and pilot-testing of a theory-guided parental HIV disclosure intervention program with two components (a primary parent component and a secondary care provider component) by culturally adapting and integrating aspects of two US-based programs that were efficacious in either helping parents to make appropriate HIV disclosure or improving mental health status of PLH and their children. Phase III will rigorously evaluate the efficacy of the proposed intervention on well-being of PLH, children and families over 36 months through a cluster randomized controlled trial involving 800 PLH (either fathers or mothers) and their children (6 to 15 years of age). The research will also identify contextual and individual factors that potentially mediate or moderate the effect of the proposed intervention on parent, child, and family outcomes. The proposed research will address the dearth of targeted interventions supporting parental efforts in disclosing their HIV status to their children by examining whether a theory-based intervention can improve parental HIV disclosure in a low-resource setting. The proposed study will also provide cross-cultural evidence to support the role of parental disclosure in the well-being of parents, children, and families.